Short-Term, Long-Term and External Memory

by Krishna on May 30, 2007

With due respect to biology, here are the types of memory that we human beings can tap into:

Short-term memory

Long-term memory

External memory

Short-term memory contains all the recent events that happened to us. For example, if I ask you how you spent yesterday, you can probably give minute details of the entire day. However, you would probably not be able to do the same for a day three months back. We can also consciously try to store important pieces of information in short-term memory. For example, if someone gives us an email address over the phone, we can remember it long enough to write it down after we put down the phone.

Although short-term memory is transient, it is essential in our life. Human beings would not be able to converse with each other if each one forgot what they or the other person said immediately after they said it. Short-term memory also provides a “working database” from which we can perform various activities at home or work. For example, a programmer needs to know all the business rules of an object when writing code.

There is also an advantage of memory being short, because we have the ability to forget things not worth remembering. Many things that happen daily, like the cars that passed you on the highway, are not important to keep thinking about. You can also utilize your short-term memory to remember key points before an important event (meeting, test, etc.) that may not be relevant afterwards.

Long-term memory is where we specialize and build deep knowledge. It contains ingrained habits that can be used to perform activities without really paying attention to them. For example, when someone asks us to multiply two numbers, we easily tap into the multiplication tables that we learnt years or decades ago. There is something interesting going on, because if you ask a child who is learning multiplication, he would find it more difficult even though he is currently learning the subject.

The reason, of course, is that the child is using short-term memory which is very fickle. But an adult has built upon the multiplication skills to learn higher concepts like algebra, geometry, trigonometry, etc. that the basic concepts are laid in stone. That is the secret behind long-term memory: The more you practice, the more you transfer from short-term memory to long-term memory.

Consider another example from sports: When you first start playing tennis, you find it tough even to keep score. Serving, volleying, etc. all are difficult. But after sometime, these become second-nature. But then you have moved to a different playing level — what will the opponent do next? How do you outlast a 5-set match? How much spin do you employ?

So every time, you are moving decisions that you had to carefully consider to a part of your brain where the decisions happen automatically. This allows you to focus on more important decisions ignoring items of less priority. This is similar to voluntary and involuntary muscles. The involuntary muscles take care of body processes like respiration, digestion, etc. without your involvement. The voluntary muscles give you the flexibility and freedom where you need it.

Finally, we have external memory which is outside our body. This primarily means knowledge in the form of paper in books, bits on electronic media, etc. where you can easily access them without having to remember. You can record both information as well as logic. By the latter, I mean, we can record how decisions are made, what processes should be followed, etc. At the same time, we are not bound to the external documentation, we still continue to have the freedom to innovate and make new rules.

Now, you are thinking, “This is all very nice, but remind me again why I am reading this.” Well, the point of this article is to ask ourselves how can we take teh greatest advantage of the different forms of memory. Here are some ideas:

Leverage external memory as much as possible so that you can focus less on trying to remember things and more on analyzing and making decisions. Don’t try to remember anything you don’t have to remember. Instead, note down where you can get to that information if you ever need it.

Keep your personal external memory as compact as possible so that recall can be faster. If you have tons of ideas written down, it is difficult to find any idea again. Instead keep only the most important points. Nowadays, Google and Wikipedia are better than the best notes you can keep. If you can find it on Google, throw away your personal notes.

If knowledge of the important aspects of your job are in your internal long-term memory, you will be really efficient at your job. And you can get around any challenges in your job by knowing where and how to locate the external memory that contains the information. For example, knowing the right query to type into Google.

Short-term memory is not that useful in real life, because you have access to huge amounts of external memory. Unfortunately, the teaching profession doesn’t really understand this properly. They keep insisting on making you remember stuff that you could look up. If you are a student, this means that you still need to work on trying to remember things that you probably don’t like just so you can obtain results necessary outside your school life.

To be an expert, you absolutely need to work on building long-term memory in the subject. The way to do this is “continuous practice”. If it is theory, read as much as you can. If it is something practical, keep doing it until you can do it in your sleep.